1. Field of the Invention
Exemplary embodiments relate to a method and apparatus for scheduling in a cellular-based device-to-device (D2D) communication that may provide scheduling of a resource used in a direct communication service between terminals using a cellular resource.
2. Description of the Related Art
Device-to-device (D2D) communication in a conventional wireless communication system has been implemented through infrastructure. A D2D communication technology involves a direct communication between terminals through going through infrastructure such as a base station, an access point (AP), and the like, and has been studied separately in the fields of proximate terminal discovery for D2D communication and communication between proximate terminals. Based on a wireless access technology, wireless fidelity (WiFi), Bluetooth, and the like, may be used, and a cellular mobile communication may be used. Because a D2D communication using an unlicensed band such as WiFi or Bluetooth is difficult to provide a scheduled and controlled service and may degrade rapidly due to interference, studies have been conducted on a D2D communication using a cellular mobile communication on a licensed band.
A D2D communication technology using a cellular mobile communication may use a radio resource used in a mobile communication network, and for this, a method in which a mobile base station allocates a resource for a D2D communication may be used.
As an example of a D2D communication, reference may be made to Korean Patent Publication No. 10-2009-0062435, published on Jun. 17, 2009, titled “Method and system for allocating resource for peer to peer communication in wireless communication system”, that may receive a peer-to-peer (P2P) communication terminal and a mobile communication resource allocation information from a base station, may scan the presence or absence of a mobile communication terminal adjacent to the P2P communication terminal using the resource allocation information, may request a P2P communication resource by transmitting a result of the scan to the base station, and may receive P2P communication resource allocation information in response to the resource request.
However, when terminals that desire to execute a direct communication belong to the same base station, this method may transmit allocated resource information to the terminals easily, but when the terminals that desire to execute a direct communication belong to different base stations, may not allocate a cellular resource efficiently.
Also, in a case of a D2D communication between terminals belonging to different cells, because a more robust modulation and coding scheme is used in consideration of passing through a cell due to a high probability that the terminal is located in the cell boundary, performance relative to an allocated radio resource may be lowered.
Accordingly, there is a demand for a method of supporting a D2D communication between terminals located in difference cells without passing through a cell.